Retractable knife



FIG. 1 is a perspective view of my retractable knife;

FIG. 2 is an elevational view of one side of the retractable knife, the other side being substantially identical thereto;

FIG. 3 is a top plan view of the device shown in FIGS. 1 and 2;

FIG. 4 is an elevational view of one end of the device;

FIG. 5 is an elevational view of the opposite end thereof; and

FIG. 6 is a perspective view of the invention with the knife blade retracted. 

The ornamental design for a retractable knife, as shown and described. 